title: Protein dilution effect on thiouracil-seroalbumin interactions.
abstract: As the spectra and binding parameters calculated for the thiouracil-albumin interaction change with the protein concentration, a human seroalbumin conformational change depending on protein concentration has been suggested. This protein-conformational change is tested by dilatometry and viscosimetry. At low concentrations, albumin showed a greater thiouracil binding capacity and a second positive peak in its interaction with the drug, detected by difference spectroscopy. Both effects are due to a monomerisation of protein dimers and not to a conformational change depending on protein concentration. This monomerisation would imply a major accessibility of thiouracil and propylthiouracil to other binding sites on HSA.
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Basque Country, Vitoria-Gasteiz, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Ochoa de Aspuru
authors.forename: M A
authors.initials: MA
authors.lastname: Marquínez
authors.forename: A M
authors.initials: AM
authors.lastname: Zatón
mesh_terms: D001665:Binding Sites; D019281:Dimerization; D006801:Humans; D011485:Protein Binding; D011487:Protein Conformation; D012709:Serum Albumin / Q000378:metabolism*; D013053:Spectrophotometry; D013889:Thiouracil / Q000378:metabolism*; D014466:Ultraviolet Rays; D014783:Viscosity
chemical_list: D012709:Serum Albumin; D013889:Thiouracil